1. What is Physical basis of Mental life?
Ans: Physical basis of mental life refers to understand the relation between body and mind, concept of nervous system and about knowing process of sensation, perception and conception in this chapter. A good physical health indicates a good mind. Again mental happiness improves our physical health. It makes our digestive, respiratory, and circulatory system of functions. In this regard, Aristotle opinion that ‘education is nothing but creation of a sound mind in the sound mind’.
2. What are the three parts of the human body?
Ans: The three parts of the human body are:
(a) Nervous system.
(b) Effectors.
(c) Receptors.
3. What is Nervous System?
Ans: The most important part of the body from the stand point of mind is the nervous system that controls the working of the whole body.
4. How nervous structure is formed?
Ans: Nervous structure is formed by innumerable small number of units called the neurons. They are spread over all part of the body and perform a network service keeping physical connection with the central nervous system.
5. What is Neurons?
Ans: Neurons are the nerve cells having different size, shape and their complexity. In brief, the structural unit of the nervous system is the neuron.
6. What are the different parts or structure of Neurons. Explain briefly.
Ans: The neuron is constituted of its different parts. These are:
(a) Cell body.
(b) Nucleus.
(c) Axon
(d) End brush
(e) Dendrite.
(f) Synapse.
The neurons are the nerve cells having different size, shape and their complexity. Each one of them is constituted of its cell body and the liquid part at its centre called nucleus. Out of the body of the neuron long fibre like part comes out to be known as axon. At the end part of axon there are a number of roots coming out, called the end brush. Again out of the cell body there are small roots coming out called the dendrites. The dendrites of one cell or neuron come in touch with the other neuron in sending the impulse is called the synapse. It is through this mechanism that the sense experience received by the body organs use to pass on the central nervous system.
7. What is Cells ?
Ans: The life of all living organisms whether it be a plant, animal or human being is made up smallest units in a human body, called Cells.
8.Why the cells are called the smallest unit of life ?
Ans: The life of all living beings is based on the working of the cells. That is why the cells are called the smallest unit of life.
9. What is Cytoplasm ?
Ans: All cells contain a fluid called cytoplasm.
Archives
10. What are the three types of Neurons ?
Ans: The three types of neurons are mentioned below:
(a) Sensory neuron:
It provides information through sense organs.
(b) Motor-neurons:
It provides involuntary actions like- breathing, eye blinking etc.
(c) Inter-neuron:
It provides messages from one neuron to another in the form of memories and thoughts.
11. What are the three types or parts of Nervous System ?
Ans: The three types or parts of nervous system are mentioned below:
(a) Autonomic nervous system.
(b) Peripheral nervous system.
(c) Central nervous system.
12. What are the two types of Autonomic Nervous System ?
Ans: The two types of autonomic nervous system are:
(a) Sympathetic.
(b) Para sympathetic.
13. What are the two types of Peripheral Nervous System ?
Ans: The two types of peripheral nervous system are:
(a) Somatic system or Cranial nerves:
It makes connection of the sense organs and the muscles of the body with the brain. There are of 12 pairs of cranial nerves working for it.
(b) Automatic system or Spinal nerve:
It is located on both sides of the spinal cord with a total of 31 pairs.
14. What are the two types of Central Nervous System ?
Ans: The two types of Central Nervous System are:
(a) Spinal Cord:
It lies within the backbone.
(b) Brain:
It is the centre of all forms of higher mental activities like- thought, intelligence, and emotional reactions.
15. What is Spinal Cord ?
Ans: Spinal Cord is the highway of the sensory and motor impulses that run to and from the brain and different parts of the body. There are 31 pairs of spinal nerves that run into the spinal cord.
16. Write two major components of Spinal Cord.
Ans: The two major components of spinal cord are:
(a) Grey matter:
It is located inside of the spinal cord.
(b) White matter:
It is located outside of the spinal cord.
17. Mention four functions of Spinal Cod.
Ans: The four functions of spinal cord are mention below:
(i) Spinal cord connects the brain with different parts of the body.
(ii) It works as a passage covering the sensory and motor impulses.
(iii) It directly controls and regulates the reflex actions like blinking of eye lids, sneezing, coughing and salivation.
(iv) It controls habitual and automatic activities like walking, running and knitting which do not require voluntary attention.
18. What is Brain ?
Ans: Brain is the most important part of the body of the central nervous system which forms higher mental activities like- thoughts, intelligence, and emotional reactions.
19. What are the different parts of the Brain ?
Ans: There are mainly three parts of the brain, namely:
(i) Cerebrum or fore brain.
(ii) Mid-brain.
(iii) Cerebellum or hind brain.
Other parts of the brain are:
(a) Thalamus.
(b) Medulla oblongata.
(c) Pons variole.
(d) Cerebral cortex.
(e) Spinal cord.
(f) Pituitary gland.
(g) Corpus callosum.
Cerebrum or Fore Brain.
It is the larger part of the brain and is the seat of all forms of higher mental activity. It is divided into two halves called right and left hemisphere. Both right and left hemisphere of this brain are connected by a thick band of fibres which is called the corpus callosum brain. Again the brain of corpus callosum covered by a layer of grey matters with convolutions or twisting folds called cerebral cortex brain. The brain of cerebral cortex brain again subdivided into four loves or areas namely:
(a) Frontal lobe.
(b) Parietal lobe.
(c) Occipital lobe.
(d) Temporal lobe.
Again there are two fissures or narrow opening on the cerebral cortex brain namely:
(a) Fissure of Orlando.
(b) Fissure of Sylvius.
Functions of Cerebrum or Fore Brain:
Functions of the cerebrum or fore brain are highly complicated which may be stored out below:
(i) It controls and regulates all parts of the body and their psycho-physical activities.
(ii) It receives information from all the receptor organs and sends messages to them.
(iii) It controls all the voluntary muscular activities and behaviour of individual.
(iv) It acts as the centre of all forms of intellectual activities like- memory, thinking, reasoning and problem solving.
(v) Feeling and emotions experienced in different situations are also originated from this part of the brain.
(vi) Different sensory areas and the lobes function as unitary whole.
Mid-Brain:
This part of the brain is located between the cerebrum and the cerebellum. It is concerned with as a relay centre of nervous impulses and also regulates nature of physical motion of the individual.
Cerebellum or Hind Brain
The cerebellum part or hind of the brain is located behind and beneath of the brain cerebrum or fore brain. Its weight is about 140 grams. This brain is mainly responsible for maintaining equilibrium of the body and steadiness of movement. It controls and co-ordinates muscular movement and also controls finer senses of art, painting, drawing, games and sports, manual dexterity and motor skill etc.
Thalamus
This part of the brain is located at the centre of the brain just below the cerebrum. There are four different parts of it named. These are:
(i) Dorsal thalamus.
(ii) Epi-thalamus.
(iii) Hypo-thalamus.
(iv) Sub-thalamus.
The dorsal thalamus part of the brain passes sensory impulses to the cerebrum which is also known as sensory centre. The other rest of the three parts acts as a motor centre and the hypothalamus part is also controls emotional experience of individual.
Medulla Oblongata
This is the upper part of the spinal cord. It contains the nerve cells and fibre tracts connecting the cerebrum. It is the centre of blood circulation and respiratory function. A person may even die if this part is injured. It controls breathing as well as heart rate. It also acts as a sleep centre.
Pons Variole
This part of the brain is a thick bundle fibres which connects the two halves to the cerebellum with the cerebrum and the medulla oblongata. It forms a bridge in between the vital parts of the brain. Here, right hemisphere of the cerebrum controls the left side and the left hemisphere controls the right side of the body.
20. Mention two basic functions of the Brain.
Ans: The two basic functions of the brain are:
(a) Cognitive functions like- learning, memory, thinking etc.
(b) The regulation of physiology of the body.
21. What are called Receptors Mechanism?
Ans: Our five sense organs that is eye, ear, nose, skin and tongue are constituted of some receptors cells capable of receiving sense impression out of stimuli in environment, So they are called the receptors.
22. What are the two types of receptors mechanism? Give example.
Ans: The two types of receptors mechanism are:
(a) External receptor: For example – eye, ear, nose, tongue and skin.
(b) Internal receptor: For example – Pain, hunger, etc.
23. What are the different parts of structure of the sense of vision eye?
Ans: There are different parts of structure of the sense of vision eye. So, the major parts of structure are mentioned below:
(a) Cornea:
The thick layer which is exists in front of the eye ball that is called Cornea.
(b) Aqueous humour:
Behind the cornea rests the transparent and liquid substance is called Aqueous humour.
(c) The Iris:
Behind the back of the humour there is exists two black circular parts, one is upper regions and second one is lower regions called iris.
(d) Pupil:
In between upper and lower regions of the two parts of the circular, there may be seen the deep black hole that is called the Pupil.
(e) The Lens:
Behind the pupil there exists a transparent and solid part that is called the lens.
(f) Ciliary Muscles:
The lens is fixed with the muscular part in all sides which is called the ciliary muscles.
(g) Vitreous Humour:
In ciliary muscles, there is exists a big circular area with jelly-like substance inside the eye ball called vitreous humour. This humour is covered by three layers.
(h) The Retina:
In the inner layer of the vitreous, there are some sensitive cells covering two-third of the area called the retina. Retina of the inner layer is constituted of two types of receptive cells called cons and rods.
(i) Choroid:
The middle layer of the vitreous humour is constituted of black substance called choroid.
(j) Sclerotic Coat:
The outer layer of the vitreous humour is constituted of white substance called sclerotic coat.
(k) Blind Spot:
The part of the retina from where the optic nerve begins is called the blind spot. Here the cons and rods are totally absent.
(l) Yellow Spot:
There is another spot on the retina where the cons and rods are more concentrated to give maximum visual senses is called yellow-spot.
N.B: The most important parts of structure of the sense of vision Eye are namely, 1. Cornea. 2. The iris. 3. The lens and 4. The retina.
24. What are the three major or main parts of structure of the sense of Ear?
Ans: The three major or main parts of the sense of ear are namely:
(a) The Outer Ear:
This part is consisted of its hole in the middle that enters into the interior region which is called Auditory canal. At the end of the canal there is the thin and sensitive membrane called the ear drum. It receives and transmits the sound wave into interior region.
(b) The Middle Ear:
It is consisted of a cave in which there are three small bones namely, hammer or ossicles, anvil or incus and stirrup or steppes bone are arranged in a chain order in this part. The stirrup bone which is touches the oval window at its inner end. Out of the middle ear, there is a tube passes down to the neck which is connected to the nose called eustachian tube.
(c) The Inner Ear:
This part is started with the oval window that connects the three semi-circular canals and the cochlea that acts like a spring. They are transmitting the impulse of sound through auditory nerve to the auditory centre of the brain.
25. What is the third major name of sensory organ?
Ans: Skin.
26. What are major four types of tactual senses of skin?
Ans: The different types of tactual senses of skin are :
(a) Pain.
(b) Pressure and touch.
(c) Warmth.
(d) Cold.
Along with these, there are some other types of tactual senses which are mentioned below:
(e) Itching.
(f) Burning.
(g) Softness.
(h) Hardness.
(i) Smoothness.
(j) Roughness.
(k) Dryness.
(l) Wetness etc. They indicate the magnitude of physical experiences of this kind being received.
Again, we should know that Physiological structure of the skin may be divided into three layer. These are:
(i) Epidermis Layer:
This type of skin is located on the surface of the body with a very thin membrane, where sensory experiences remain absent.
(ii) Dermis Layer:
It is located under the epidermis which gives different cutaneous senses.
(iii) Fat Layer:
It is located under the dermis as a thick layer of the muscles called fat layer. It gives rise to physical weight of individual.
Other parts of skin are:
(iv) Oil Gland.
(v) Hair Follicle.
(vi) Blood Vessels.
(v) Sweet Gland.
Point to be remember:
- Each eye is about 25 mm in diameter and weighs about 7gm.
- The sense vision of eye is called the queen of receptors.
- Skin is the third major sensory organ and it gives cutaneous sensation.
- It serves as the alternative sense organ to seeing.
- As a specific sense organ, skin cover the whole body organism but it does not give equal sensory stimulation to all the parts.
- Outer parts of the body, skin sensation is found to be more intense than the inner parts of the organism.
Recent Comments